firast up, that's the way it works with eggdrops, it's nothing to do with mIRC itself.
secondly this is what i used for dcc chats
on 1:INPUT:=:{
if ($left($1,1) != /) {
haltdef
msg $active $1-
}
}
then in my /msg alias i have this line
if ($chr(61) isin $1) { echo -ai25 $+ $calc($len($1) + 8) 13<15 $+ $me $+ 13> $2- | .msg $1- }